Mechanism for adjusting the brush height in carpet sweepers



Aug. 25, 1964 J. M. HlMES ETAL MECHANISM FOR ADJUSTING THE BRUSH HEIGHT IN CARPET SWEEPERS Filed June 24, 1965 2 Sheets-Sheet 1 INVENTORS JOHN M- H M JERRY W. PoAD ATTORNEY Aug. 25, 1964 J. M. HIMES ETAL 3,145,405

MECHANISM FOR ADJUSTING THE BRUSH HEIGHT IN CARPET SWEEPERS Filed June 24, 1963 2 Sheets-Sheet 2 INVENTORS JOHN M. 'hmF- c1 4 JRRY W-POHD ATTORNEY United States Patent 3,145,405 MECHANISM FUR. ADJUSTENG THE BRUSH HEEGHT IN CARPET SWEEPERS John M. Himes, Hartford, and Jerry W. Pond, Milwaukee,

Wis., assignors to E. R. Wagner Manufacturing Company, Milwaukee, Wis, a corporation of Wisconsin Filed June 24, 1963, Ser. No. 289922 9' Claims. (Cl. 15-41) This invention relates to improvements in mechanisms for adjusting the brush height in carpet sweepers.

The principal object of this invention is to provide a dial operated carpet sweeper brush height adjustment mechanism which will permit several intermediate height settings between amaxi-mum height, as required for thick nap carpets, and between a minimum height, as required for close nap carpets or bare-floors.

A further object of this invention is to provide a dial operated carpet sweeper brush height adjustment mechanism in which the knob of the dial is located on the top exterior wall of the carpet sweeper housing to render the same easily visible and accessible to the user.

A still further object. of this invention is to provide an adjustment mechanism having the above described advantageswithout sacrificing or impairing any of the desirable features of the heretofore known high quality carpet sweepers, and without significantly increasing the cost of acarpct sweeper by virtue of the adjustment mechanism.

These-objects are attained by a mechanism which is responsive to the selective turning of a knob located on the top exterior of the carpet sweeper housing and by means of whicha crankshaft may be actuated to limit or vary. the lowest position of the brush. By limiting only the lower position, it is possible to still maintain the advantage of spring. loading the brush to thereby prevent stalling of the sweeper upon encountering some irregularities of the carpet or small object inadvertently left thereon.

Other. objects and advantages will be pointed out in, or be apparent from, thespecification and claims, as will obvious modifications of the single embodiment shown in the drawings, in which:

FIG. 1 is a top plan View of a carpet sweeper embodying the present invention, with only a fragment of the handle being shown;

FIG, 2 is a vertical cross sectional View of the carpet sweeper shown in FIG. 1 in which one of the end bells has been removed to show. the floor wheels and the brush;

FIG. 3 is a view in vertical cross section taken on line 33 of FIG. 1 showing the brush height adjustment mechanism at the highest brush height setting, the floor wheels and brush pulley being superimposed and shown in dashed lines to better illustrate the cooperation of these parts;

FIG. 4 is a view as shown in FIG. 3, but having the brush height adjustment at the lowest brush height setting;

FIG. 5 is a fragmentary cross sectional view taken on line 5'5"of-FIG. 3;

FIG. 6 isa fragmentary side view of the knob and the cam housing;

FIG. 7 is a cross sectional view of the cam housing;

FIGS. 8 and 9 show the cam in side elevation;

FIG. 10 is a bottom plan view of the knob;

FIG. 11 is a view taken on line ii-11 of FIG. 7;

FIG. 12 is a fractional bottom plan view of the cam and adjustment rod with part of the cam housing being broken away; and

FIG. 13 is a side view of the brush slide.

The drawings illustrate a carpet sweeper of which the basic elements and principles of operation are well-known in the art and are in general disclosed in the U.S. patent projection 42.

issued to Swift Miller Patent Number 2,121,880. The invention resides in replacing the brush height adjustment disclosed. in the aforementioned patent by an adjustment mechanism which is responsive to the turning of aknob It? to any one of a number of positions between the highest and lowest settings to thereby provide corresponding height settings of the brush 12 of the sweeper. Further, the mechanism is designed to permit the knob 10 to be centrally located on the top exterior surface of the carpet sweeper housing 14.

The carpet sweeper has floor engaging wheels 16' which with sockets 25 of the'brush axle 26are attached by pins Ztitoeach of the bell caps-3h disposed on the sides of the housing. Each slide is provided with elongated slot' 32 for reception of the pin 28 tothereby permit some limited vertical motion of the slide. Each slide is further guided by a contoured and depressed portion 34- in the bell cap. It is of note that by virtue of the contoured portion a-corresponding elongated slot 38 has to be pro vided in the bell cap for reception ofthe trunnionv 24.

As best seen from FIG. 3 a wire spring 38 is retained within the bell cap by eyelet members 49 and engages a projection 42 of the slideto exert a normally downward bias thereon.

In normal operation of the sweeper the spring 38 pushes the brushil downwardly to cause the same to enter the carpet and thereby cause the brush bristles to bend slightly and give a flicking action. The spring allows the brush to rise for any condition whichwouldrequire the bristlesto bend more than planned, and in this manner permits the-brush to ride over the obstruction. In absence'of this feature the pulley would-tend to bind and prevent rotationof both floor wheelsld.

As best seen from FIGS. 3 and i, the lowerlimit of the vertical travel of the brush is controlled by the wedge sur-- facei i. of lever 45. which engages the bottom side of:the

By varying the position of the wedge surface 44, the effective brush height will be correspondingly varied while stillmaintaining the feature ofpermitting. the brush to rise against the bias of the spring38 upon encountering an obstruction on the floor.

An adjustment rod 48 is transversely disposedwithin the housing andretainedforrotation around its longitudinal axis by sidewall 59 of the housing. A crank arm 52.:

is provided on each end of the adjustment rod andisengaged with one end of the lever 46 to impart motion thereto upon rotation of the adjustment rod around its longitudinal axis.(indicated at A in FIGS.- 2 and; 3).

54 which is engaged by the pin 28. As is. apparent, when comparing FEGS. 2 and 3, the rotation of the crank arm in a clockwise direction when viewed in these figures will cause a downward movement of the wedge surface 44 thereby permitting the spring 33 to bias the brush 12 to its lowermost position. Also a rotation in the opposite direction will cause the wedge surface 44 to force the projection 42 of the axle link upwardly and thus limit the amount of vertical travel permitted by the brush. It is apparent that the vertical location of the wedge surface 44 is dependent upon the degree of turn of the crankshaft 52 around its axis and that therefore the brush height (i.e. vertical location of projection 42) can be set Patented Aug. 25, 1964 j The other end of the lever is provided with an elongated slotv 3 at any desired position between those shown in FIG. 4 and FIG. 3.

At its center the adjustment rod 48 is provided with a transversely extending section 54 which is engaged by a cam 56 and may be moved in response to the rotation of the cam between the two positions shown in FIG. 7.

The knob 10 is rotatably secured to the top surface 14 of the carpet sweeper housing and is secured to the cam 56 by means of three nibs 58 which engage corresponding apertures in the bottom face 60 of the cam and thus cause the knob and cam to rotate as a unit. The knob overlies a dial face 62 on which the various brush heights are indicated and is provided with a pointer 64 to show the position of the brush. The brush height settings on the dial may be, of course, indicated in the terms of the type of nap for which the particular brush height setting is suitable, as for example, close nap, medium nap, and thick nap. Resilient element 66 having a projection 68 is provided on the bottom face 70 of the knob and cooperates with apertures 72 in the housing wall to permit indexing of the knob. The projection engages the apertures with suificient force to prevent unintended movement of the dial during normal operation of the carpet sweeper, yet permits easy turning of the dial by hand when it is desired to change the brush height settings. A stop member 74 cooperates with a groove 76 in the knob to limit the rotary motion of the knob between the high brush and the low brush settings.

To prevent dust and dirt from interfering with the operation of the cam, the cam and its related structure are enclosed in a cam housing 78. The housing is comprised of two sheet metal members 80 and 82 which are secured to each other by means of tabs 86. One of the members is provided with notches 88 which receive the adjustment rod.

From the above description it should be apparent that the brush height adjustment mechanism embodying the present invention is operable to effectively limit the vertical downward travel of the brush 12 without impairing the spring loading of the brush which is required to prevent stalling when encountering an obstruction in the path of the carpet sweeper.

Further it is of note that the brush settings may be varied by the easily accessible and visible knob 10 which is located on the top surface of the housing and may be indexed to provide incremental adjustment of the brush height as required for the particular surface desired to be swept.

Although but one embodiment of the present invention has been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.

We claim:

1. A carpet sweeper comprising, a wheeled housing, a brush and two slides, said brush being rotatably mounted at each end on one of said slides and said slides being secured for limited vertical motion to said housing to thereby permit said brush to ride over small obstructions which might be encountered on the surface to be swept, biasing means urging said brush and slides downwardly, stop means limiting the extent of permissible downward travel of said brush, a knob rotatably carried by said housing, and a crankshaft operably connected to said stop A means and said knob to vary the position of said stop means to a plurality of positions to thereby selectively change the lowest position to which said brush may be biased by said biasing means yet to permit the upward travel required to ride over said small obstructions.

2. A carpet sweeper according to claim 1 having indexing means adapted to retain said knob on any one of a number of preselected positions.

3. A carpet sweeper according to claim 2 wherein said knob is located between the ends of said crankshaft and wherein said knob carries cam means operable to rotate said crankshaft upon rotation of said knob.

4. A carpet sweeper according to claim 3 wherein said cam means comprises a cylindrical member having a slanted end portion, said end portion engaging a section of said crankshaft which extends transversely to the longitudinal axis of said crankshaft.

5. A carpet sweeper comprising, a wheeled housing, a brush and two slides, said brush being rotatably mounted at each end on one of said slides and said slides being secured for limited vertical motion to said housing to thereby permit said brush to ride over small obstructions which might be encountered on the surface to be swept,

. biasing means urging said brush and slides downwardly,

two control levers each operable to engage one of said slides and limit the extend of their downward travel, a crankshaft carried by said housing and secured at each of its ends to one of said control levers, a knob mounted on said housing and having cam means operable to rotate said crankshaft in response to rotation of said knob, said crankshaft changing the position of said control levers in response to the rotation of said knob to thereby change the lowest position to which said brush may be biased.

6. A carpet sweeper according to claim 5 wherein said knob is located between the two ends of said crankshaft and is mounted in an upwardly facing position.

7. A carpet sweeper according to claim 6 wherein said cam means engage a portion of said crankshaft which extends transversely to the longitudinal axis of said crankshaft.

8. A carpet sweeper according to claim 7 wherein said knob has indexing means for retaining said knob in any one of a plurality of preselected positions between the high and low positions of said brushes.

9. A carpet sweeper comprising, a housing, a brush, said brush being rotatably mounted in said housing, brush driving wheels carried in said housing and vertically movable relative to said brush, spring means for biasing said -relative vertical movement, laterally spaced stop means limiting the extent of said relative vertical movement, a knob rotatably carried by said housing, and a crankshaft operably connected to said each of said spaced stop means and said knob and rotatable by said knob to vary the position of said stop means to a plurality of positions to thereby selectively change the limits of said relative vertical movement.

References Cited in the file of this patent UNITED STATES PATENTS 554,817 Friant et al. Feb. 18, 1896 2,121,880 Miller June 28, 1938 2,239,276 Smith Apr. 22, 1941 2,793,378 Williams et al. May 28, 1957 3,034,163 Stevens et al. May 15, 1962 

1. A CARPET SWEEPER COMPRISING, A WHEELED HOUSING, A BRUSH AND TWO SLIDES, SAID BRUSH BEING ROTATABLY MOUNTED AT EACH END ON ONE OF SAID SLIDES AND SAID SLIDES BEING SECURED FOR LIMITED VERTICAL MOTION TO SAID HOUSING TO THEREBY PERMIT SAID BRUSH TO RIDE OVER SMALL OBSTRUCTIONS WHICH MIGHT BE ENCOUNTERED ON THE SURFACE TO BE SWEPT, BIASING MEANS URGING SAID BRUSH AND SLIDES DOWNWARDLY, STOP MEANS LIMITING THE EXTENT OF PERMISSIBLE DOWNWARD TRAVEL OF SAID BRUSH, A KNOB ROTATABLY CARRIED BY SAID HOUSING, AND A CRANKSHAFT OPERABLY CONNECTED TO SAID STOP MEANS AND SAID KNOB TO VARY THE POSITION OF SAID STOP MEANS TO A PLURALITY OF POSITIONS TO THEREBY SELECTIVELY CHANGE THE LOWEST POSITION TO WHICH SAID BRUSH MAY BE BIASED BY SAID BIASING MEANS YET TO PERMIT THE UPWARD TRAVEL REQUIRED TO RIDE OVER SAID SMALL OBSTRUCTIONS. 